The present invention is related to the protection and guidance of optical fiber cables. More specifically, the invention is a device for retaining the bend of one or more optical fiber cables at a safely large radius while guiding them through a hole in a panel, while routing them along the surface of a panel, or while storing them on a panel. It has a particular application in the telecommunications industry.
Fiber optic cables that are routed to and within equipment must be protected from being bent too sharply as might occur at sharp corners and edges or when excess cable is hanked for storage. Such sharp bending can cause cable fibers to be physically damaged by overstressing, and can cause functional failure of the fibers by changing internal optical properties at those bends. Specifically, loss of proper internal reflection of light traveling through the fiber as it reaches the overly sharp bend will be realized. It is therefore advantageous to keep a cable from being bent below its minimum bend radius even temporarily while installing and storing cable, and to provide some physical support to limit the bend radius during use.
One common method to avoid sharp bends is to spirally wrap cables around cylindrical tubing of a sufficient outside diameter, which tubing is then routed along the intended path of the optical cable. Although this method does ensure that the cable bend will never be sharper than the tubing""s outside diameter, installing the tubing with the spirally wrapped cable is a tedious process. It is also expensive to tubing along the entire length of the cable""s pathway just to ensure a sufficient radius only at the bend locations.
Some devices that support cable around curved surfaces only locally at the bend locations are known and include, for example, those shown in U.S. Pat. Nos. D427,897; 5,530,787; 5,724,469; 5,917,982; 5,937,131; 5,946,440; 5,995,699; 6,002,089; and 6,049,040. Such devices can be attached to panels along the intended route of the trays, but are only designed to address guiding of cable along its route or the storage of excess cable in a hank. It is therefore desirable to provide a singular device for retaining the bend of one or more optical fiber cables at a safely large radius either while guiding them through a hole in a panel, while routing them along the surface of a panel, or while storing them on a panel.
An additional problem faced when routing fiber optic cables through holes in panels is that the edges of such holes are often sharp or jagged. These edges can cause damage to or cut through the cable. It is therefore desirable to provide a means for protecting the cable from contact with the hole edge.
The present invention is a device for fixing to a panel or such and having a curved surface with a radius of curvature that is larger than the specified minimum bend radius for fiber optic cable. The device is adapted to support cables as they meander between and within equipment, whether on or through panel surfaces, while retaining the bend of the cables at a safely large radius.
In addition to including means for being affixed to the panel, the invention further includes means for covering the hole""s edge. This is particularly useful in that it protects the cable from the usually sharp hole edge while guiding the cable through the hole.
The device is also adapted for providing a spool for storing excess cable, when four of the devices are provided and affixed to the panel, arranged in rectangular fashion. This ensures that the stored coil of excess cable cannot be bent sharper than the specified minimum bend radius for the cable.
Additionally, the invention is adapted to grasp the edges of panel holes and to grasp certain walls protruding from panels so that fasteners are not required. This feature allows for easier, faster, and more reliable assembly to the panel while reducing part count in most cases.
It is therefore an object of the present invention to provide an improved device for protecting, supporting and guiding fiber optic cable.
It is a further object to provide such a device which supports cable as it runs along panel surfaces and through panel holes.
It is a further object to provide such a device that is adaptable to form a cable storage spool.
It is a further object to provide such a device that protects cable that is routed through sharp edged panel holes from those sharp edges.
It is a further object to provide such a device that can be affixed to panels and panel holes without auxiliary fasteners.
Further objects and advantages of the present invention will become apparent upon review of the following description of the preferred embodiment and accompanying drawings thereof.